The absence of Sol Campbell is a serious blow, though Wenger can take some comfort from the fact the defender's deputy, Pascal Cygan, has reserved his best games for the European stage.
He will need to be pretty sharp tonight because Emmanuel Olisadebe is making a habit of breaching Arsenal's rearguard. The Polish striker scored the equalising goal after 81 minutes in Athens a fortnight ago and also found the net when the Greeks lost 2-1 to Arsenal in October 2001.
Panathinaikos always travel with boundless enthusiasm - and of course generate enormous support among London's Greek fraternity - but they have never won on seven visits to England. Their last trip resulted in a 5-0 defeat at Old Trafford last season.
Wenger can be sure Panathinaikos will work hard to prevent his team building any rhythm in their play. "They're well organised and committed," he said. "They can frustrate people. We saw the Greeks do that in the European Championship."
The absence of the injured Brazilians Edu and Gilberto Silva means that 17-year-old Spanish midfielder Francesc Fabregas will play the key creative role alongside Patrick Vieira in the heart of Wenger's team.
Last season he became Arsenal's youngest player and youngest scorer, and in eight first-team starts this season has looked a mature and influential figure in midfield. "He's an intelligent passer," said Wenger.
Spared the Old Trafford defeat and most of the draw with Southampton, Fabregas might just provide the fresh, creative impetus that opens doors for Thierry Henry and Dennis Bergkamp tonight.
"It takes time to absorb the shock of the defeat at Old Trafford and find a new momentum," said Wenger.
Let's hope they find it tonight because anything less than a win could seriously jeopardise their Champions League prospects.
